Reading the political runes is a fool's errand in 2018. So, how can we assess the risk of a no-deal Brexit? There is no doubt that the consensus view among businesses is that it has gone from a theoretical but marginal possibility to a non-negligible outcome. It is now a focus for many contingency plans.

Unusually in Brexit world, the law can give us some useful pointers as to how we got here and where we are going. I offer you six legal steps to a no-deal Brexit.

  1. No-deal Brexit is the do-nothing outcome. The UK will cease to be a member of the EU on 29 March 2019, unless the UK asks for an extension of time and each one of the EU27 agrees. And thus the common and reciprocal arrangements and international trade agreements to which the UK is party today as an EU member will cease to apply.
  2. Nearly is not good enough. 80% of a withdrawal agreement may be agreed, but nothing is legally effective until it is all agreed, and the NI border back-stop remains a fundamental sticking point. (But is it legally required?)
  3. There are two routes to a no-deal Brexit. (1) The EU and the UK Government cannot agree a deal. If the Prime Minister cannot recommend a deal by mid-January 2019, she is required by statute to report this to Parliament and set out the proposed way forward - for a meaningful vote. (2) The UK Parliament does not like the deal. Theresa May is required by statute to present the deal to Parliament for a meaningful vote. The deal cannot be ratified without Parliament's approval. It is difficult to find a parliamentary majority in favour of anything in Westminster.
  4. Parliamentary disapproval is a shortcut to a general election. In either scenario, if the Prime Minister does not win the vote, she has one more chance to find a compromise. If she loses that, it is almost inevitably a confidence vote.
  5. Confidence lost, election follows. If the Prime Minister loses a confidence vote, the Conservatives will have one last chance to form a new government that can command a majority within seven days. If that fails, a General Election automatically follows.
  6. A five-week wait. The minimum legal period between calling a General Election and polling day is five working weeks. Brexit day may have come and gone. Now go back to point 1.